Add fabricated RRO generation to libidmap2
Fabricated Runtime Resource Overlays are overlays that are generated
at runtime and are stored in the data/ partition.
The system can fabricate RROs at runtime to dynamically theme the
device. Idmaps can now be created from APK RROs and fabricated RROs.
Rather than operating on ApkAssets, libidmap2 now operates on abstract
resource "containers" that supply resource values. Target resource
containers implement methods needed to query overlayable and target
overlay information. Currently only APKs can be loaded as target
resource containers. Overlay resource containers implement methods to
supply the mapping of target resource to overlay value and other
overlay information.
The format of a fabricated RRO is as follows:
0x00 - 0x04 : fabricated overlay magic (always FRRO)
0x04 - 0x08 : file format version
0x08 - 0x0c : crc of version + proto data
0x0c - EOF : proto fabricated overlay data
The magic is used to quickly detect if the file is a fabricated overlay.
The version is incremented whenever backwards incompatible changes are
made to the proto file format. Idmap must always be able to upgrade
fabricated overlays from previous versions to new versions, so all
previous versions must be checked into the tree.
Bug: 172471315
Test: libidmap2_tests && libandroidfw_tests
Change-Id: I4c9f29da278672e5695fb57d131a44c11a835180
diff --git a/cmds/idmap2/libidmap2/ResourceMapping.cpp b/cmds/idmap2/libidmap2/ResourceMapping.cpp
index 46eeb8e..3bbbf24 100644
--- a/cmds/idmap2/libidmap2/ResourceMapping.cpp
+++ b/cmds/idmap2/libidmap2/ResourceMapping.cpp
@@ -30,19 +30,12 @@
using android::base::StringPrintf;
using android::idmap2::utils::BitmaskToPolicies;
-using android::idmap2::utils::IsReference;
-using android::idmap2::utils::ResToTypeEntryName;
using PolicyBitmask = android::ResTable_overlayable_policy_header::PolicyBitmask;
using PolicyFlags = android::ResTable_overlayable_policy_header::PolicyFlags;
namespace android::idmap2 {
namespace {
-
-#define REWRITE_PACKAGE(resid, package_id) \
- (((resid)&0x00ffffffU) | (((uint32_t)(package_id)) << 24U))
-#define EXTRACT_PACKAGE(resid) ((0xff000000 & (resid)) >> 24)
-
std::string ConcatPolicies(const std::vector<std::string>& policies) {
std::string message;
for (const std::string& policy : policies) {
@@ -55,11 +48,11 @@
return message;
}
-Result<Unit> CheckOverlayable(const LoadedPackage& target_package,
+Result<Unit> CheckOverlayable(const TargetResourceContainer& target,
const OverlayManifestInfo& overlay_info,
const PolicyBitmask& fulfilled_policies,
const ResourceId& target_resource) {
- static constexpr const PolicyBitmask sDefaultPolicies =
+ constexpr const PolicyBitmask kDefaultPolicies =
PolicyFlags::ODM_PARTITION | PolicyFlags::OEM_PARTITION | PolicyFlags::SYSTEM_PARTITION |
PolicyFlags::VENDOR_PARTITION | PolicyFlags::PRODUCT_PARTITION | PolicyFlags::SIGNATURE |
PolicyFlags::CONFIG_SIGNATURE;
@@ -68,8 +61,13 @@
// the overlay is preinstalled, signed with the same signature as the target or signed with the
// same signature as reference package defined in SystemConfig under 'overlay-config-signature'
// tag.
- if (!target_package.DefinesOverlayable()) {
- return (sDefaultPolicies & fulfilled_policies) != 0
+ const Result<bool> defines_overlayable = target.DefinesOverlayable();
+ if (!defines_overlayable) {
+ return Error(defines_overlayable.GetError(), "unable to retrieve overlayable info");
+ }
+
+ if (!*defines_overlayable) {
+ return (kDefaultPolicies & fulfilled_policies) != 0
? Result<Unit>({})
: Error(
"overlay must be preinstalled, signed with the same signature as the target,"
@@ -77,367 +75,112 @@
" <overlay-config-signature>.");
}
- const OverlayableInfo* overlayable_info = target_package.GetOverlayableInfo(target_resource);
- if (overlayable_info == nullptr) {
+ const auto overlayable_info = target.GetOverlayableInfo(target_resource);
+ if (!overlayable_info) {
+ return overlayable_info.GetError();
+ }
+
+ if (*overlayable_info == nullptr) {
// Do not allow non-overlayable resources to be overlaid.
return Error("target resource has no overlayable declaration");
}
- if (overlay_info.target_name != overlayable_info->name) {
+ if (overlay_info.target_name != (*overlayable_info)->name) {
// If the overlay supplies a target overlayable name, the resource must belong to the
// overlayable defined with the specified name to be overlaid.
return Error(R"(<overlay> android:targetName "%s" does not match overlayable name "%s")",
- overlay_info.target_name.c_str(), overlayable_info->name.c_str());
+ overlay_info.target_name.c_str(), (*overlayable_info)->name.c_str());
}
// Enforce policy restrictions if the resource is declared as overlayable.
- if ((overlayable_info->policy_flags & fulfilled_policies) == 0) {
+ if (((*overlayable_info)->policy_flags & fulfilled_policies) == 0) {
return Error(R"(overlay with policies "%s" does not fulfill any overlayable policies "%s")",
ConcatPolicies(BitmaskToPolicies(fulfilled_policies)).c_str(),
- ConcatPolicies(BitmaskToPolicies(overlayable_info->policy_flags)).c_str());
+ ConcatPolicies(BitmaskToPolicies((*overlayable_info)->policy_flags)).c_str());
}
return Result<Unit>({});
}
-// TODO(martenkongstad): scan for package name instead of assuming package at index 0
-//
-// idmap version 0x01 naively assumes that the package to use is always the first ResTable_package
-// in the resources.arsc blob. In most cases, there is only a single ResTable_package anyway, so
-// this assumption tends to work out. That said, the correct thing to do is to scan
-// resources.arsc for a package with a given name as read from the package manifest instead of
-// relying on a hard-coded index. This however requires storing the package name in the idmap
-// header, which in turn requires incrementing the idmap version. Because the initial version of
-// idmap2 is compatible with idmap, this will have to wait for now.
-const LoadedPackage* GetPackageAtIndex0(const LoadedArsc& loaded_arsc) {
- const std::vector<std::unique_ptr<const LoadedPackage>>& packages = loaded_arsc.GetPackages();
- if (packages.empty()) {
- return nullptr;
+std::string GetDebugResourceName(const ResourceContainer& container, ResourceId resid) {
+ auto name = container.GetResourceName(resid);
+ if (name) {
+ return *name;
}
- int id = packages[0]->GetPackageId();
- return loaded_arsc.GetPackageById(id);
+ return StringPrintf("0x%08x", resid);
}
-
-Result<std::unique_ptr<Asset>> OpenNonAssetFromResource(const ResourceId& resource_id,
- const AssetManager2& asset_manager) {
- auto value = asset_manager.GetResource(resource_id);
- if (!value.has_value()) {
- return Error("failed to find resource for id 0x%08x", resource_id);
- }
-
- if (value->type != Res_value::TYPE_STRING) {
- return Error("resource for is 0x%08x is not a file", resource_id);
- }
-
- auto string_pool = asset_manager.GetStringPoolForCookie(value->cookie);
- auto file = string_pool->string8ObjectAt(value->data);
- if (!file.has_value()) {
- return Error("failed to find string for index %d", value->data);
- }
-
- // Load the overlay resource mappings from the file specified using android:resourcesMap.
- auto asset = asset_manager.OpenNonAsset(file->c_str(), Asset::AccessMode::ACCESS_BUFFER);
- if (asset == nullptr) {
- return Error("file \"%s\" not found", file->c_str());
- }
-
- return asset;
-}
-
} // namespace
-Result<ResourceMapping> ResourceMapping::CreateResourceMapping(const AssetManager2* target_am,
- const LoadedPackage* target_package,
- const LoadedPackage* overlay_package,
- size_t string_pool_offset,
- const XmlParser& overlay_parser,
- LogInfo& log_info) {
- ResourceMapping resource_mapping;
- auto root_it = overlay_parser.tree_iterator();
- if (root_it->event() != XmlParser::Event::START_TAG || root_it->name() != "overlay") {
- return Error("root element is not <overlay> tag");
+Result<ResourceMapping> ResourceMapping::FromContainers(const TargetResourceContainer& target,
+ const OverlayResourceContainer& overlay,
+ const OverlayManifestInfo& overlay_info,
+ const PolicyBitmask& fulfilled_policies,
+ bool enforce_overlayable,
+ LogInfo& log_info) {
+ auto overlay_data = overlay.GetOverlayData(overlay_info);
+ if (!overlay_data) {
+ return overlay_data.GetError();
}
- const uint8_t target_package_id = target_package->GetPackageId();
- const uint8_t overlay_package_id = overlay_package->GetPackageId();
- auto overlay_it_end = root_it.end();
- for (auto overlay_it = root_it.begin(); overlay_it != overlay_it_end; ++overlay_it) {
- if (overlay_it->event() == XmlParser::Event::BAD_DOCUMENT) {
- return Error("failed to parse overlay xml document");
- }
-
- if (overlay_it->event() != XmlParser::Event::START_TAG) {
+ ResourceMapping mapping;
+ for (const auto& overlay_pair : overlay_data->pairs) {
+ const auto target_resid = target.GetResourceId(overlay_pair.resource_name);
+ if (!target_resid) {
+ log_info.Warning(LogMessage() << target_resid.GetErrorMessage());
continue;
}
- if (overlay_it->name() != "item") {
- return Error("unexpected tag <%s> in <overlay>", overlay_it->name().c_str());
+ if (enforce_overlayable) {
+ // Filter out resources the overlay is not allowed to override.
+ auto overlayable = CheckOverlayable(target, overlay_info, fulfilled_policies, *target_resid);
+ if (!overlayable) {
+ log_info.Warning(LogMessage() << "overlay '" << overlay.GetPath()
+ << "' is not allowed to overlay resource '"
+ << GetDebugResourceName(target, *target_resid)
+ << "' in target: " << overlayable.GetErrorMessage());
+ continue;
+ }
}
- Result<std::string> target_resource = overlay_it->GetAttributeStringValue("target");
- if (!target_resource) {
- return Error(R"(<item> tag missing expected attribute "target")");
- }
-
- Result<android::Res_value> overlay_resource = overlay_it->GetAttributeValue("value");
- if (!overlay_resource) {
- return Error(R"(<item> tag missing expected attribute "value")");
- }
-
- auto target_id_result =
- target_am->GetResourceId(*target_resource, "", target_package->GetPackageName());
- if (!target_id_result.has_value()) {
- log_info.Warning(LogMessage() << "failed to find resource \"" << *target_resource
- << "\" in target resources");
- continue;
- }
-
- // Retrieve the compile-time resource id of the target resource.
- uint32_t target_id = REWRITE_PACKAGE(*target_id_result, target_package_id);
-
- if (overlay_resource->dataType == Res_value::TYPE_STRING) {
- overlay_resource->data += string_pool_offset;
- }
-
- if (IsReference(overlay_resource->dataType)) {
- // Only rewrite resources defined within the overlay package to their corresponding target
- // resource ids at runtime.
- bool rewrite_reference = overlay_package_id == EXTRACT_PACKAGE(overlay_resource->data);
- resource_mapping.AddMapping(target_id, overlay_resource->data, rewrite_reference);
- } else {
- resource_mapping.AddMapping(target_id, overlay_resource->dataType, overlay_resource->data);
+ if (auto result = mapping.AddMapping(*target_resid, overlay_pair.value); !result) {
+ return Error(result.GetError(), "failed to add mapping for '%s'",
+ GetDebugResourceName(target, *target_resid).c_str());
}
}
- return resource_mapping;
+ auto& string_pool_data = overlay_data->string_pool_data;
+ if (string_pool_data.has_value()) {
+ mapping.string_pool_offset_ = string_pool_data->string_pool_offset;
+ mapping.string_pool_data_ = std::move(string_pool_data->data);
+ mapping.string_pool_data_length_ = string_pool_data->data_length;
+ }
+
+ return std::move(mapping);
}
-Result<ResourceMapping> ResourceMapping::CreateResourceMappingLegacy(
- const AssetManager2* target_am, const AssetManager2* overlay_am,
- const LoadedPackage* target_package, const LoadedPackage* overlay_package, LogInfo& log_info) {
- ResourceMapping resource_mapping;
- const uint8_t target_package_id = target_package->GetPackageId();
- const auto end = overlay_package->end();
- for (auto iter = overlay_package->begin(); iter != end; ++iter) {
- const ResourceId overlay_resid = *iter;
- Result<std::string> name = utils::ResToTypeEntryName(*overlay_am, overlay_resid);
- if (!name) {
- continue;
+Result<Unit> ResourceMapping::AddMapping(
+ ResourceId target_resource,
+ const std::variant<OverlayData::ResourceIdValue, TargetValue>& value) {
+ if (target_map_.find(target_resource) != target_map_.end()) {
+ return Error(R"(target resource id "0x%08x" mapped to multiple values)", target_resource);
+ }
+
+ // TODO(141485591): Ensure that the overlay type is compatible with the target type. If the
+ // runtime types are not compatible, it could cause runtime crashes when the resource is resolved.
+
+ if (auto overlay_resource = std::get_if<OverlayData::ResourceIdValue>(&value)) {
+ target_map_.insert(std::make_pair(target_resource, overlay_resource->overlay_id));
+ if (overlay_resource->rewrite_id) {
+ // An overlay resource can override multiple target resources at once. Rewrite the overlay
+ // resource as the first target resource it overrides.
+ overlay_map_.insert(std::make_pair(overlay_resource->overlay_id, target_resource));
}
-
- // Find the resource with the same type and entry name within the target package.
- const std::string full_name =
- base::StringPrintf("%s:%s", target_package->GetPackageName().c_str(), name->c_str());
- auto target_resource_result = target_am->GetResourceId(full_name);
- if (!target_resource_result.has_value()) {
- log_info.Warning(LogMessage()
- << "failed to find resource \"" << full_name << "\" in target resources");
- continue;
- }
-
- // Retrieve the compile-time resource id of the target resource.
- ResourceId target_resource = REWRITE_PACKAGE(*target_resource_result, target_package_id);
- resource_mapping.AddMapping(target_resource, overlay_resid,
- false /* rewrite_overlay_reference */);
- }
-
- return resource_mapping;
-}
-
-void ResourceMapping::FilterOverlayableResources(const AssetManager2* target_am,
- const LoadedPackage* target_package,
- const LoadedPackage* overlay_package,
- const OverlayManifestInfo& overlay_info,
- const PolicyBitmask& fulfilled_policies,
- LogInfo& log_info) {
- std::set<ResourceId> remove_ids;
- for (const auto& target_map : target_map_) {
- const ResourceId target_resid = target_map.first;
- Result<Unit> success =
- CheckOverlayable(*target_package, overlay_info, fulfilled_policies, target_resid);
- if (success) {
- continue;
- }
-
- // Attempting to overlay a resource that is not allowed to be overlaid is treated as a
- // warning.
- Result<std::string> name = utils::ResToTypeEntryName(*target_am, target_resid);
- if (!name) {
- name = StringPrintf("0x%08x", target_resid);
- }
-
- log_info.Warning(LogMessage() << "overlay \"" << overlay_package->GetPackageName()
- << "\" is not allowed to overlay resource \"" << *name
- << "\" in target: " << success.GetErrorMessage());
-
- remove_ids.insert(target_resid);
- }
-
- for (const ResourceId target_resid : remove_ids) {
- RemoveMapping(target_resid);
- }
-}
-
-Result<ResourceMapping> ResourceMapping::FromApkAssets(const ApkAssets& target_apk_assets,
- const ApkAssets& overlay_apk_assets,
- const OverlayManifestInfo& overlay_info,
- const PolicyBitmask& fulfilled_policies,
- bool enforce_overlayable,
- LogInfo& log_info) {
- AssetManager2 target_asset_manager;
- if (!target_asset_manager.SetApkAssets({&target_apk_assets})) {
- return Error("failed to create target asset manager");
- }
-
- AssetManager2 overlay_asset_manager;
- if (!overlay_asset_manager.SetApkAssets({&overlay_apk_assets})) {
- return Error("failed to create overlay asset manager");
- }
-
- const LoadedArsc* target_arsc = target_apk_assets.GetLoadedArsc();
- if (target_arsc == nullptr) {
- return Error("failed to load target resources.arsc");
- }
-
- const LoadedArsc* overlay_arsc = overlay_apk_assets.GetLoadedArsc();
- if (overlay_arsc == nullptr) {
- return Error("failed to load overlay resources.arsc");
- }
-
- const LoadedPackage* target_pkg = GetPackageAtIndex0(*target_arsc);
- if (target_pkg == nullptr) {
- return Error("failed to load target package from resources.arsc");
- }
-
- const LoadedPackage* overlay_pkg = GetPackageAtIndex0(*overlay_arsc);
- if (overlay_pkg == nullptr) {
- return Error("failed to load overlay package from resources.arsc");
- }
-
- size_t string_pool_data_length = 0U;
- size_t string_pool_offset = 0U;
- std::unique_ptr<uint8_t[]> string_pool_data;
- Result<ResourceMapping> resource_mapping = {{}};
- if (overlay_info.resource_mapping != 0U) {
- // Use the dynamic reference table to find the assigned resource id of the map xml.
- const auto& ref_table = overlay_asset_manager.GetDynamicRefTableForCookie(0);
- uint32_t resource_mapping_id = overlay_info.resource_mapping;
- ref_table->lookupResourceId(&resource_mapping_id);
-
- // Load the overlay resource mappings from the file specified using android:resourcesMap.
- auto asset = OpenNonAssetFromResource(resource_mapping_id, overlay_asset_manager);
- if (!asset) {
- return Error("failed opening xml for android:resourcesMap: %s",
- asset.GetErrorMessage().c_str());
- }
-
- auto parser =
- XmlParser::Create((*asset)->getBuffer(true /* wordAligned*/), (*asset)->getLength());
- if (!parser) {
- return Error("failed opening ResXMLTree");
- }
-
- // Copy the xml string pool data before the parse goes out of scope.
- auto& string_pool = (*parser)->get_strings();
- string_pool_data_length = string_pool.bytes();
- string_pool_data.reset(new uint8_t[string_pool_data_length]);
-
- // Overlays should not be incrementally installed, so calling unsafe_ptr is fine here.
- memcpy(string_pool_data.get(), string_pool.data().unsafe_ptr(), string_pool_data_length);
-
- // Offset string indices by the size of the overlay resource table string pool.
- string_pool_offset = overlay_arsc->GetStringPool()->size();
-
- resource_mapping = CreateResourceMapping(&target_asset_manager, target_pkg, overlay_pkg,
- string_pool_offset, *(*parser), log_info);
} else {
- // If no file is specified using android:resourcesMap, it is assumed that the overlay only
- // defines resources intended to override target resources of the same type and name.
- resource_mapping = CreateResourceMappingLegacy(&target_asset_manager, &overlay_asset_manager,
- target_pkg, overlay_pkg, log_info);
+ auto overlay_value = std::get<TargetValue>(value);
+ target_map_.insert(std::make_pair(target_resource, overlay_value));
}
- if (!resource_mapping) {
- return resource_mapping.GetError();
- }
-
- if (enforce_overlayable) {
- // Filter out resources the overlay is not allowed to override.
- (*resource_mapping)
- .FilterOverlayableResources(&target_asset_manager, target_pkg, overlay_pkg, overlay_info,
- fulfilled_policies, log_info);
- }
-
- resource_mapping->target_package_id_ = target_pkg->GetPackageId();
- resource_mapping->overlay_package_id_ = overlay_pkg->GetPackageId();
- resource_mapping->string_pool_offset_ = string_pool_offset;
- resource_mapping->string_pool_data_ = std::move(string_pool_data);
- resource_mapping->string_pool_data_length_ = string_pool_data_length;
- return std::move(*resource_mapping);
-}
-
-OverlayResourceMap ResourceMapping::GetOverlayToTargetMap() const {
- // An overlay resource can override multiple target resources at once. Rewrite the overlay
- // resource as the first target resource it overrides.
- OverlayResourceMap map;
- for (const auto& mappings : overlay_map_) {
- map.insert(std::make_pair(mappings.first, mappings.second));
- }
- return map;
-}
-
-Result<Unit> ResourceMapping::AddMapping(ResourceId target_resource, ResourceId overlay_resource,
- bool rewrite_overlay_reference) {
- if (target_map_.find(target_resource) != target_map_.end()) {
- return Error(R"(target resource id "0x%08x" mapped to multiple values)", target_resource);
- }
-
- // TODO(141485591): Ensure that the overlay type is compatible with the target type. If the
- // runtime types are not compatible, it could cause runtime crashes when the resource is resolved.
-
- target_map_.insert(std::make_pair(target_resource, overlay_resource));
-
- if (rewrite_overlay_reference) {
- overlay_map_.insert(std::make_pair(overlay_resource, target_resource));
- }
return Unit{};
}
-Result<Unit> ResourceMapping::AddMapping(ResourceId target_resource,
- TargetValue::DataType data_type,
- TargetValue::DataValue data_value) {
- if (target_map_.find(target_resource) != target_map_.end()) {
- return Error(R"(target resource id "0x%08x" mapped to multiple values)", target_resource);
- }
-
- // TODO(141485591): Ensure that the overlay type is compatible with the target type. If the
- // runtime types are not compatible, it could cause runtime crashes when the resource is resolved.
-
- target_map_.insert(std::make_pair(target_resource, TargetValue{data_type, data_value}));
- return Unit{};
-}
-
-void ResourceMapping::RemoveMapping(ResourceId target_resource) {
- auto target_iter = target_map_.find(target_resource);
- if (target_iter == target_map_.end()) {
- return;
- }
-
- const auto value = target_iter->second;
- target_map_.erase(target_iter);
-
- const ResourceId* overlay_resource = std::get_if<ResourceId>(&value);
- if (overlay_resource == nullptr) {
- return;
- }
-
- auto overlay_iter = overlay_map_.equal_range(*overlay_resource);
- for (auto i = overlay_iter.first; i != overlay_iter.second; ++i) {
- if (i->second == target_resource) {
- overlay_map_.erase(i);
- return;
- }
- }
-}
-
} // namespace android::idmap2